Question

if the car travels around the curve at speed 2v, which free body diagram could represent the forces acting on the car? consider only the forces or force components in the plane of the image. assume the car does not slide. choose 1 answer: a (diagram with f_n, f_{f,s}, f_g) b (diagram with f_n)

Explanation:

Step1: Analyze Forces on Car

When a car moves in a curve, centripetal force is needed. Forces on the car: gravitational force ($F_g$ downward), normal force ($F_n$), and static friction ($F_{f,s}$) which provides centripetal force (toward center of curve).

Step2: Evaluate Diagrams

• Diagram A: Has $F_g$ (down), $F_n$ (upward - angled, balancing $F_g$), and $F_{f,s}$ (toward center, providing centripetal force).
• Diagram B: Lacks $F_g$ and friction (needed for centripetal force when speed > critical speed for banked road, but here, since it’s a curve (likely unbanked or banked but speed 2v needs friction), A includes necessary forces.

Answer:

A. The free - body diagram with $F_g$ downward, $F_n$ upward - angled, and $F_{f,s}$ toward the center of the curve.